import java.util.Scanner;

public class SwitchExcise3 {
    public static void main(String[] args) {
        char type;

        System.out.println("请输入等级：");
        Scanner sc=new Scanner(System.in);
        type=sc.next().charAt(0);
        switch (type) {
            case 'A':
                System.out.println("优秀");
                break;

            case 'B':
            case 'C':
                System.out.println("良好");
                break;

            case 'D':
            case 'E':
                System.out.println("及格");
                break;

            case 'F':
                System.out.println("不及格");
                break;

        } }
}
